Facebook has started to answer questions about whether and how Russian accounts may have bought ads intended to disrupt the EU referendum in 2016.

Facebook told the UK's election watchdog that a single Russian group spent just $1 on Brexit ads, which were seen by a maximum of 200 people.

A politician leading a separate inquiry into fake news slammed this response, and said Facebook needed to do more work to uncover new Russian-funded ads and accounts.

Facebook has claimed that Russia barely interfered with the UK's referendum on leaving the EU in 2016, with a single group spending less than $1 (75p) on ads that were seen by 200 British people at most.

Specifically, Facebook found that the Russian-backed Internet Research Agency spent this tiny amount of money on ads to UK audiences during the period of the referendum. The three ads focused on immigration, and were targeted at US and UK audiences.

He claimed Facebook had only looked at the activity of one Russian group which had already been active in the US presidential election. He said the company had done no further work to look for Russian meddling in the Brexit vote.

Here's what he said, emphasis ours:

"In their response to the Electoral Commission, Facebook responded only with regards to funded advertisements to audiences in the UK from the around 470 accounts and pages run by the Russian based Internet Research Agency, which had been active during the US Presidential election.

"It would appear that no work has been done by Facebook to look for Russian activity around the EU referendum, other than from funded advertisements from those accounts that had already been identified as part of the US Senate's investigation. No work has been done by Facebook to look for other fake accounts and pages that could be linked to Russian backed agencies and which were active during the EU referendum, as I requested."

Collins noted that Facebook had run its own standalone analysis to identify tens of thousands of fake pages in relation to the French presidential election earlier this year. He added: "They should do the same looking back at the EU referendum and not just rely on external sources referring evidence of suspicious activity back to them."

Collins said: "Are we to believe that Russian backed targeting of voters through social media with fake news was limited only to Twitter during the referendum, when both Twitter and Facebook had been used in the USA during the Presidential election?"

A Facebook spokesman said: "We met with Mr Collins on Wednesday and shared the information we provided to the Electoral Commission.

"The Electoral Commission is the official regulator for elections in the UK. We have responded fully to their enquiries and will continue to work closely with them on any further queries."